Genetics And Plant Breeding - Study Mode
[#296] A pair of genes are linked if their recombination frequency in test cross is
Correct Answer
(D) Less than 50%
Explanation
Solution: A pair of genes are linked if their recombination frequency in the test cross is Less than 50%. If the genes are far apart on a chromosome or different chromosomes, the recombination frequency is 50%. In this case, the inheritance of alleles at the two loci is independent. If the recombination frequency is less than 50% we say the two loci are linked.
[#297] The number of double crosses will be equal to
Correct Answer
(B) $$frac{{{ ext{n}}left( {{ ext{n}} - 1}
ight)left( {{ ext{n}} - 2}
ight)left( {{ ext{n}} - 3}
ight)}}{8}$$
[#298] Which of the following is a remarkable feature of photosynthesis?
Correct Answer
(D) Light energy is converted into chemical energy
Explanation
Solution: Light energy is converted into chemical energy is a remarkable feature of photosynthesis. Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored in carbohydrate molecules, such as sugars and starches, which are synthesized from carbon dioxide and water hence the name photosynthesis, from the Greek word phōs, "light", and synthesis, "putting together".
[#299] The analogue of 5-bromouracil is
Correct Answer
(D) Thymine
Explanation
Solution: The analogue of 5-bromouracil is Thymine. 5-Bromouracil (BrU) is a base analogue of thymine (T) which can be incorporated into DNA. 5 bromouracil pairs with thymine because the analog of thymine has a higher tendency to form an enol tautomer with its resembling base that is thymine.
[#300] In mitosis, longest phase is
Correct Answer
(C) Prophase
Explanation
Solution: In mitosis, the longest phase is the prophase. The first and longest phase of mitosis is prophase. During prophase, chromatin condenses into chromosomes, and the nuclear envelope breaks down. In animal cells, the centrioles near the nucleus begin to separate and move to opposite poles of the cell.